Half of the permanent steel plates being used to fix a cracked beam on the Interstate 40 bridge between Memphis and West Memphis are in place, the Tennessee Department of Transportation said Friday.
The remaining four plates should be delivered today, and miscellaneous steel components will arrive next week, according to an update from Nichole Lawrence, the agency's community relations officer for western Tennessee.
The six-lane Interstate 40 bridge over the Mississippi River has been closed since May 11, when a crack was found in a tie girder (beam) during a routine inspection. The 48-year-old structure is officially known as the Hernando de Soto Bridge, or "the new bridge."
Traffic is being routed to the four-lane Interstate 55 bridge, 3 miles to the south. The 71-year-old bridge on I-55 also is known as the Memphis and Arkansas Bridge, or to Memphians as just "the old bridge."
Dave Parker, a spokesman for the Arkansas Department of Transportation, said the fractured section of the I-40 bridge's tie girder was removed Monday. He said the section removed was a few feet long.
Transportation officials haven't provided a concrete timeline, but they estimate completion of the bridge repairs could take until the end of July. Work to repair the bridge has been going on 24 hours a day, seven days a week, according to Friday's update.
Drilling, bolting and torquing are ongoing, according to Friday's update. More than 4,400 permanent bolts have been used to connect the plates.
So far, 108,000 pounds of structural steel plating have been added to the tie girder, according to the update. More than 1.2 million pounds of tension have been removed from the fractured section and put on the composite section.
The crack on the Hernando de Soto Bridge, a tied-arch span, was found on a steel beam that connected chords to the arch. When the beam cracked, the load that was once carried by the beam shifted to other parts of the bridge.
The Tennessee Transportation Department oversees repairs of the shared bridge, while the Arkansas department is responsible for bridge inspections. Kiewit Infrastructure Group was contracted for the repairs.
The Arkansas Trucking Association said the repurposing of traffic lanes around the bridge has cut the detour time from 84 minutes to 15. That means the detour is costing the trucking industry less than $1 million a day, compared with the $2.4 million a day when the detour took 84 minutes.
Since the I-40 bridge closed on May 11, the trucking industry has absorbed over $70 million in unanticipated costs, according to a news release from Kelly Cargill Crow, vice president for the Arkansas association.
"When the bridge first closed, delays were regularly exceeding an hour," said Shannon Newton, president of the association. "Now thanks to ARDOT's traffic engineering, implementing strategic lane shifts, that delay is down to only 15 minutes."
The state Transportation Department implemented a series of lane changes in West Memphis on June 9 to improve the traffic flow.
"In just the two weeks since ARDOT reconfigured traffic in West Memphis, we have saved roughly $21.9 million in expenses as the estimated cost per day decreased from $2.4 million to $936,000," according to the release. "Trucking is still losing nearly a million dollars a day, but these improvements are proving significant to an industry that is already struggling to meet demand."
Data provided by the American Transportation Research Institute indicates the average cost of operating a truck to be $71.78 an hour or $1.20 a minute, according to the news release.
Truck traffic over the Mississippi River has decreased only slightly from 26,500 carriers per day down to 23,500, according to the release.
"Using the latest [research] data, we estimate those 3,000 trucks that are re-routing 60 miles or more from the I-55 bridge are losing $513,000 per day in lost time and increased mileage while the cost of the 15-minute delay for the 23,500 trucks using the I-55 bridge is an estimated $423,000," Newton said.
In-depth inspections of the bridge continue, according to the Tennessee update.
The crack was discovered May 11, but a photo from 2019, confirmed by transportation officials to be authentic, shows the crack has been around for potentially years. Another photo, currently being reviewed by state and federal officials, appears to show a crack as far back as 2016.
The discovery led the Arkansas department to fire the inspection team leader for missing the crack on previous inspections.